Packaging structure of an inkjet print head chip and method for making the same

Abstract

A packaging structure for inkjet print head chips and the method for manufacturing them are disclosed. An inkjet print head chip with several contact nodes on its surface is mounted onto a substrate through chip bonding to form a packaging structure. Since the contact nodes are not limited to the border of the chip, the number of pins on the chip can be increased. The packaging method can be combined with the semiconductor processes to lower the cost. Moreover, the chip mounting packaging structure has the advantages of self-alignment and high reliability.

What is claimed is:  
     
         1 . An inkjet print head chip packaging structure, comprising: 
 a chip, which has a plurality of fluid channels for a fluid to pass through, the surface of the chip having a plurality of conductive contact nodes;    a substrate, whose surface has a plurality of pads corresponding to the conductive contact nodes, each of the pads being connected to the associated conductive contact node to mount the chip on the substrate surface and the plurality of fluid supply regions of the substrate thereby providing the fluid to flow through the fluid channels in the chip; and    an adhesive material, which fills the junction area between the chip surface and the substrate surface.    
     
     
         2 . The packaging structure of  claim 1 , wherein the conductive contact nodes form an arrayed conductive contact nodes with more than one row.  
     
     
         3 . The packaging structure of  claim 1 , wherein each of the fluid channels has a heater to produce thermal bubbles that drive the fluid.  
     
     
         4 . The packaging structure of  claim 1 , wherein the conductive contact nodes are higher than the junction surface structure of the chip and the substrate.  
     
     
         5 . The packaging structure of  claim 1 , wherein the adhesive material is a thermally cured polymer.  
     
     
         6 . The packaging structure of  claim 1 , wherein the conductive contact node is formed by combining a metal pad on the chip surface and the associated solder ball.  
     
     
         7 . The packaging structure of  claim 6 , wherein the solder ball is made using a method selected from half-tone printing, electroplating, and non-electroplating.  
     
     
         8 . The packaging structure of  claim 6 , wherein the material of the solder ball is an Sn—Pb alloy.  
     
     
         9 . The packaging structure of  claim 1 , wherein the chip surface further contains a barrier and a conductive layer above the barrier layer, the top of the conductive layer being connected to the conductive contact node.  
     
     
         10 . The packaging structure of  claim 9 , wherein the material of the barrier layer is selected from the group consisting of Ti, Cr, and their alloys.  
     
     
         11 . The packaging structure of  claim 9 , wherein the material of the conductive layer is selected from the group consisting of Cu, Ni, and their alloys.  
     
     
         12 . A method for manufacturing an inkjet print head chip packaging, comprising the steps of: 
 providing a chip with a plurality of fluid channels for the fluid to flow through, the chip surface having a plurality of conductive contact nodes;    forming a plurality of pads on a substrate surface, the substrate having a plurality of fluid supply regions;    aligning and combining each of the conductive contact nodes on the chip surface with the associated pad on the substrate surface, so that the chip is mounted on the substrate surface and the fluid supply regions in the substrate are in fluid communications with the fluid channels in the chip; and    filling an adhesive material in the junction area of the chip and the substrate, the adhesive material stopping at the border of each of the fluid supply regions due to the boundary effects.    
     
     
         13 . The method of  claim 12 , wherein the conductive contact nodes form an arrayed conductive contact nodes with more than one row.  
     
     
         14 . The method of  claim 12 , wherein the conductive contact nodes are higher than the junction surface structure of the chip and the substrate.  
     
     
         15 . The method of  claim 12 , wherein the adhesive material is a thermally cured polymer.  
     
     
         16 . The method of  claim 12 , wherein the step of filling an adhesive material in the junction area of the chip and the substrate fills the mobile fluid in the junction area using the capillary effect.  
     
     
         17 . The method of  claim 12 , wherein the conductive contact node is formed by combining a metal pad on the chip surface and the associated solder ball.  
     
     
         18 . The method of  claim 17 , wherein the solder ball is made using a method selected from half-tone printing, electroplating, and non-electroplating.  
     
     
         19 . The method of  claim 17 , wherein the material of the solder ball is an Sn—Pb alloy.  
     
     
         20 . The method of  claim 12 , wherein the chip surface further contains a barrier and a conductive layer above the barrier layer, the top of the conductive layer being connected to the conductive contact node.  
     
     
         21 . The method of  claim 20 , wherein the material of the barrier layer is selected from the group consisting of Ti, Cr, and their alloys.  
     
     
         22 . The method of  claim 20 , wherein the material of the conductive layer is selected from the group consisting of Cu, Ni, and their alloys.